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By F. S. Crawford

A large number of operators of various industries in the United States do not appear to realize the great returns in dollars and cents which result from intelligently directed safety work . Managers of co 1 mines , metal mines , open-pit mines , quarries , steel mills , cement mills , oil rei meries , iron works , or other industrial operations , should by all means realize the great waste resulting from accidents , in order to appreciate the necessity for a continuous accident -prevention policy . While the prevention of accidents is worth while from the humanitarian standpoint alone , it has an equally important economic side , and before our mining industrial operations will be made as safe as they should be , it is apparent that this dollars and cents viewpoint must be given full recognition in order to bring before many of the men who run the industries the great importance of this phase of industrial management . : There is a tendency upon the part of the opera or who has not given thought to the cost of accidents ( and there are many mining operators of this type) to insure his company against compensation losses and against catastrophes for which he can secure insurance , and think he has done his duty ar an executive . Even though industrial operations were not compelled to pay compensation , and even if the management were not moved by humanitarian motives to try to stop accidents , it would pay many times over to carry on accident prevention work vigorously and continuously. : In some parts of the United States , the state compensation and insurance requirements are such that the operator does not receive a reduction in his insurance rate per men employed upon having made safety installations or upon having achieved a reduction of accidents in his plant . Under such conditions the management frequently does not feel encouraged to emert much effort in bettering the accident rate . However , when the responsible officials of a company realize the much greater harm to an operation which results from doing no accident - prevention work , and the great benefit in reduced costs which usually follows effective safety work , they should be inclined to do almost everything possible to reduce accidents , regardless of considerations as to accident compensations . There are enough indirect costs resulting from accidents to wreck many types of business ; excessive accidents result in disorganization and failure , while immunity from accidents usually means a smoothly running efficient organization .

Sep 1, 1930

By H. B. Brunot, L. C. IlsLey

The chief object of the Electrical Section of the United States Bureau of Mines is the study of causes and means of preventing accidents resulting from the use of electricity in mines . A large part of this work for the last 20 years has been the inspection and testing of mining equipment under the provisions of schedules which give the minimum requirements considered essential for the safety of equipment intended for use at or near the working faces of dusty or gassy mines . During the first few years of this work , particular attention was paid to the explosionproof features of the various accessories such as motors , controllers , and other parts . The knowledge of the essentials necessary for safe designs of enclosures has since been augmented by field experience and by data obtained in testing a large number and variety of designs . With our present knowledge it would seem that a disproportionate stress was placed on making the various enclosures explosionproof , but not enough thought was given to the danger from wiring and connections outside of explosionproof enclosures . The list of equipment that has met minimum requirements for safety and has been approved as permissible by the Bureau of Mines includes storage - battery locomotives , power trucks , drills , loading machines , conveyors , cutting machines , room hoists , pumps , concrete mixers , and rock-dusting machines . The wiring on some of the machines is comparatively simple and sometimes , except for the trailing cable , may be entirely within the explosionproof enclosures . In general , there is outside wiring between enclosures , and on the larger machines the wiring may be extensive and complicated . In considering the safety of wiring for mining machinery , attention must be given the severe service and unfavorable surroundings imposed by mining conditions . Some of the matters that require consideration are : ground . The lack of care of the exterior wiring to be expected in the average mine . The lack of adequate periodic inspection of the wiring . The absence of adequate facilities for satisfactory inspection and repairs under- The severe conditions of moisture , dirt , mechanical injury , and low voltage encountered in mining service .

Apr 1, 1931

By Leland A. Yerkes

Refining aluminum from crude aluminum alloys by the subhalide reaction was investigated to develop a method of producing aluminum by means other than electrolysis of its oxide. The best materials and design for the apparatus and also optimum operating conditions, including temperature, pressure, vapor flow rate, and composition of alloy charge were studied. In the subhalide process, aluminum-trihalide vapor reacts with aluminum in the alloy under high temperature and low pressure, forming volatile aluminum monohalide which reverts to aluminum metal and aluminum trihalide on cooling. The only halide used in this investigation was aluminum trichloride. The crude aluminum-silicon alloys used as the principal raw material contained from 21.9 to 36 percent aluminum, and significant quantities of iron and titanium. These alloys were produced by direct electric smelting of clays. Graphite tubing that was heated by an induction coil proved to be satisfactory material for the laboratory reactor chamber, Enclosed in an insulated glass or quartz pipe, the reactor was used in both vertical and horizontal positions with various baffle and tray arrangements for directing the trihalide vapor both over and through the alloy. Aluminum trichloride vapor was generated in the sublimer at one end of the glass pipe, passed into the reactor where contact was made with the crude alloy, and aluminum monochloride gas was formed. When the gaseous mixture of aluminum monochloride and unreacted tri-chloride passed out of the reactor and entered the condenser, the gases were cooled to 900° C. or less, causing the monochloride to disproportionate into aluminum and aluminum trichloride vapor. The aluminum was deposited on the condenser walls while the aluminum trichloride vapor was carried out of the condenser and into the opposite end of the glass pipe where it solidified on the cooled copper coils.

Jan 1, 1961

By S. H. Ash

[On December 2, 1932, the Governor of California called upon the representatives of the mining industry of the State to attend a meeting at Sacramento to discuss ways and means of assisting is relieving some of its perplexing and extremely distressing problems, particularly the mounting cost of accidents which faces the industry with an industrial insurance rate for classification of $11.85 per $100 of pay roll, effective January 1, 1033. The significance of this fact is at once apparent when it is realized that the classification rates per $100 of pay roll for mining have steadily increased for some time, as follows: $3.91 in 1924, $5.54 in 1925 and 1926, $8.04 in 1927, $8.53 in 1928, $9.05 in 1929, $9.42 in 1930, $10.54 in 1931, $10.99 in 1952, and $11.85 in 1133. In other words, the cost rates have acre than doubled, wile statistics indicate that the accident rates nave shown an entirely different trend. At the meeting mentioned, one of the management officials sounded an effective keynote when he declared that a spade should be called: a spade. The perplexing problems of any industry can be approached best and remedies applied if that policy is kept to the front. It is appropriate to mention that high accident rates and a decrease in wages in recent years have unquestionably accounted in part for a unit cost rate, on a pay-roll basis; it also is well to explain that the policy years3 1926 to 1930, inclusive, are the years on which the accident-cost experience for 193: is based. That accident rates :lave not undergone the expected beneficial chance in California's experience is apparent in the words of a Bureau of Mines report:4]

Jan 1, 1933

By L. J. Kane

Chemical processes using coal often require economical removal of dust from high-temperature gases. Laboratory-scale investigations by the Federal Bureau of Mines have shown that an aluminum silicate fiber is suitable for filtering dust from gases at 1,800° F. The effects of the bulk density of the filter, rate of gas-flow, concentration of dust in the filter, fiber diameter, depth of filter, and concentration of dust in the feed gas on removal efficiency, pressure drop, and capacity of the filter to hold dust were studied. The laboratory filters were difficult to construct because the fibers were longer than the tube diameter. This caused irregular distribution of fiber that permitted dust-laden gases to leak through channels developed in the filter. Leaks also formed between the filter and the tube wall, but this was minimized by improved filter design. However, edge leaks and leaks through channels in the filter probably would be insignificant in properly constructed filters of industrial size. As the concentration of dust in the filter increased, the efficiency of the low-density filters decreased, contrary to expectations, probably because a higher percentage of the dust passed through channels that developed in the filter. The efficiency of high-density filters, however, increased with the concentration of dust in the filter. Results indicate that loosely packed filters would have a longer life than tightly packed filters at the expense of efficiency. As regeneration or replacement of stationary filters is difficult and expensive, loose filters would be best for filtering gases containing much dust. Gases containing little dust may be cleaned with tightly packed filters to obtain higher efficiency. For either type of filter, precleaning with cyclone separators or other means is advisable.

Jan 1, 1960

By Robert E. Barieau

This report describes a method for treating pressure-volume-temperature (PVT) data obtained with a Burnett compressibility apparatus. The method makes use of a general nonlinear least-squares technique developed at the Bureau of Mines Helium Research Center. It is assumed that an adequate functional form is available for the expression of the compressibility factor as a function of either the molal density or the pressure. The functional form of the compressibility factor can be either linear or nonlinear in the parameters to be evaluated. Formulas are given for calculating variances and covariances of all parameters evaluated and for calculating the variance of calculated quantities of interest.

Jan 1, 1967

By J. C. Franklin

A 32-channel continuous monitoring system has been developed to monitor radiation working level (WL), fan operation, and air door position. The system consists of a surface receiver unit and an underground transmitter that is connected to the various monitors. A continuous WL monitor used with the system can generate alarms at two different WL readings. One of these levels is variable from 0.00 to 0.99 WL and generates an alarm on the surface receiver. The other level, fixed at 1.0 WL, generates an underground alarm in the vicinity of the monitor. The detectors for fan operation and air door position work on the principle of a completed circuit to the underground transmitter (multiplexer). When the circuit is broken, as is the case when a fan is off or an air door is open, an alarm is generated at the surface receiver. This alarm remains in effect until the circuit is completed, signifying the fan has been turned on or the air door has been closed.

Jan 1, 1982

This volume summarizes the contract work performed over a nine-month period by Westinghouse Electric Corporation on a Cost Plus Fixed Fee Contract for the Department of Interior's Bureau of Mines. The contract has been extended primarily to carry out improvements recommended for equipment produced under the contract for communicating with and locating trapped miners. These improvements will enhance the performance and utility of this equipment for operational use in actual mine emergencies. An additional complete set of the equipment will also he furnished to the Bureau under this extension. The work of the basic contract was to design, produce and test hardware in accordance with the Westinghouse response to a Bureau of Mines Request for Proposal which was based technically on recommendations of a study performed for the Bureau by the National Academy of Engineering (NAE). The NAE study made suggestions for new equipment in three areas of need:

Jan 1, 1971

By C. H. Gorski

Evaluation of raw materials for mineral wool is one phase of the Bureau of Mines broad program for the more effective utilization: of our mineral resources. The experimental work and test-evaluation results on several raw materials as useful components for the production of mineral wool are presented in this report. Samples from all sections of the United States, including copper slag from Tacoma, Wash., pebble phosphate slime from Florida, and granites from Massachusetts and Minnesota, have been blown into mineral wool successfully in the laboratory tests. Maximum conservation of the Nation's mineral and manpower resources requires maximum utility of those resources. Al though the domestic reserves of oil, gas, and coal are tremendous, judicious use of these fuels through the use of proper insulation will insure the highest thermal efficiency. The effectiveness of mineral wool as a heat-insulating material has assumed an increasingly important role in the national economy, and it has become a fuel saver in countless applications. The most immediate concern to many is the use of mineral wool in the home, which promotes uniform temperature and minimizes drafts by reducing heat transfer through the walls, ceiling, and floors. There are, however, many industrial and commercial uses that require large volumes of mineral wool each year.

Jan 1, 1951

By W. T. Abel

Laboratory tests were conducted with a closed, recycling system to evaluate the effectiveness of solid-in-gas suspensions as heat transport mediums. Micronized graphite in helium or nitrogen was circulated by a centrifugal compressor to determine the feasibility of the method and heat transfer capabilities of the mediums. Suspensions were circulated without plugging or eroding the compressor or piping. At low flowrates and light (0.1 to 0.2 volume-percent) graphite loadings, slightly less power was required to transport a given amount of heat with suspensions than with helium alone. Graphite deposition on the heat exchange surfaces of the cooler decreased the heat transfer effectiveness at higher solids concentration. Efforts to eliminate deposition are described.

Jan 1, 1963

By Donna lynne Anderson

This report documents the status of a laser-based underground guidance system for tracking and controlling the movements of underground mobile mining equipment. This research is part of a multiple project effort at the U.S. Bureau of Mines to increase mine safety and efficiency by developing technology for computer-assisted mining. Guidance systems, which can track and control the movements of underground mining equipment, are essential during computer-assisted mining operations. A continuous mining machine at the Bureau's surface test facility served as the test-bed for initial development and experimentation of this guidance system. Subsequently, a continuous mining machine in an underground mine served as the platform for in-mine experimentation. The first section of this report includes details of the laser sensors, communication network, and computer hardware. The next section includes experimental results, which show the system capable of accurately tracking and controlling the tram maneuvers of a continuous miner underground. The final section discusses conclusions and recommendations.

Jan 1, 2010

By Raymond Derzay

This publication is intended to be of value to the mineral industry in establishing and maintaining effective programs for preventing noise-induced hearing loss. Factors involved in this loss and the need for and the requirements of an effective hearing conservation program are discussed. The legal and legislative history of compensation for hearing loss is briefly reviewed. A review of statutes is not attempted since several States have recently modified) or are in the process of modifying their laws regarding permissible noise exposures) required hearing protection) and/or compensation for hearing loss. A review of other aspects of the problem of industrial noise in terms of medical, physiological) and psychological frames of reference is included. A hearing conservation program is described in detail. Appendixes detailing the names and addresses of a few equipment suppliers are included. References are provided for those who may wish to delve more deeply into the medical, technical, and scientific considerations of noise and its effect on man.

Jan 1, 1972

By Robert J. Tuchman

This report presents the origins of the Bureau of Mines and the evolution of the Pittsburgh Research Center from its inception to its present form. Areas of major research emphasis over the years, as well as administrative reorganizations, are discussed.

Jan 1, 1998

By S. S. Todd

[The purpose of this investigation was to obtain, heat-of-formation values a four Common titanates and, to conjunction with other requisite data, to derive free-energy-of-formation values In tem peratures in the range of 1,600°-1,800° K. T ht four titanites are tricalcium ?ditanite !['a¬spheremr?raritanar( rint-tir.rniurn rill( 1 This rc rr,rt sul,rlc?nu?nIs :r },r; vinu~ hul,lrc.irse,n3i n wlti h eht-rmnnIN-ti i n c {ar.a ai?rc? pu -,csseeri (or, 11 in(c-rnxiLIic co mrc+unrls conraininL~ rir:,niurrl. 'f Lac? !1~:)mc? c?xpcrirnc'ntnl n-ut rhod w,i. rna~loycul. lic?.ats of for rn:ltion of rlre comi?c,unr4~ it 29S.N. ut re mca,urc?,l by tioItl[ion e':iIorrr)utrv, using a ctrneaR }ryrlrc,fllanric-hY rir~chlorie- ,aci l mixttrrt .is rhr c-zle~rinrrrric- fluid and rc.actic~n rtu,liura}.]

Jan 1, 1956

By Lindsay D. Norman

Four chloride and seven fixed-nitrogen processes for recovering manganese from domestic resources are described. The chloride processes are divided into two classes (leaching and chloridization) depending upon the major operation responsible for converting the manganese minerals to the chloride from which manganese oxide products are obtained. The fixed nitrogen processes, all of which yield high-grade manganese oxide products, are essentially either leaching or roasting processes. The 11 processes include HC1 leach, HC1 chloridization, HC1 chloride volatilization, CaC12 chloride volatilization, NO2 leach, HNO3 leach, HNO3 ?NO2 leach, H3 ?CO2-H2O system leach, (NH4)2SO4 leach, (NH4)2SO4 roast , and ammonium salt roast .

Jan 1, 1963

By Lindsay D. Norman

Four chloride and seven fixed-nitrogen processes for recovering manganese from domestic resources are described. The chloride processes are divided into two classes (leaching and chloridization) depending upon the major operation responsible for converting the manganese minerals to the chloride from which manganese oxide products are obtained. The fixed nitrogen processes, all of which yield high-grade manganese oxide products, are essentially either leaching or roasting processes. The 11 processes include HC1 leach, HC1 chloridization, HC1 chloride volatilization, CaC12 chloride volatilization, NO2 leach, HNO3-NO2 leach, NH3-CO2-H2O system leach, (NH4)2SO4 leach, (NH4)2SO4 roast, and ammonium salt roast.

Jan 1, 1963

By A. L. Toenges, F. A. Jones, J. N. Sxudder, E. R. Maize

"INTRODUCTION This report is the second of a series of studies of analysis of energy requirements and characteristics of various machines used in the production of coal in underground mines and the losses in distribution of energy to these machines. The test equipment used in these studies is described in Report of Investigations 3615. 7/ The preliminary study data and results of tests made on various types of mechanical-leading cutting, and transporting equipment at two mines. This report is analysis of the energy requirements of the energy requirements of the underground equipment of a third mine. An analysis of the use of energy and its distribution usually requires in a saving in energy consumption and the reduction of hazards. The distribution system should be designed to supply energy effectively and study for the efficient operation of all machines."

Feb 1, 1943

By Walter R. Storms

The Iron Mountain tungsten deposits first were visited by a field party of the Federal Geological Survey in May 1942 while beryllium deposits in that district' were being examined . Later they were examined by F. A. Rutledge , an engineer of the Bureau of Mines , and an exploration project was recommended , work upon which began in March 1943 and was terminated in April 1943 after intensive trenching and sampling had been completed .

Mar 1, 1947

By Eric E. Ungar

Some fundamental facts regarding noise are summarized. Guidelines for reducing plant noise are indicated, and simple means are discussed for determining, whether quieting of specific equipment items will reduce plant noise significantly. Design and installation recommendations are made for quieting chutes by means of dams, impact cushioning pads, impact shields, and damping materials, and for quieting; screens by means of resilient decks, lined screen bottoms, drive mechanism enclosures, and side plate additions. A brief account is appended of the wear and productivity performance of resilient materials observed in three cleaning plants.

Jan 1, 1976

By H. Dolezal

An investigation was made on the use of magnesium for the direct reduction of rutile to make low-cost, offgrade titanium which could be upgraded to an acceptable grade of metal by electrorefining. Reductions made with charges containing magnesium chloride under hydrogen yielded products with oxygen con-tests close to the theoretical equilibrium composition. Two reduction products were made from rutile for use in electrorefining amenability tests: (1) a product from reduction in an inert atmosphere which contained 88.9 percent titanium and 4.42 percent oxygen, and (2) a product from reduction in a hydro-gen atmosphere which contained 92.5 percent titanium and 2.40 percent oxygen. Reduction products obtained under both of these conditions were amenable to electrorefining.

Jan 1, 1965